Depends, but a 320 is plenty engine
trib said:
Looks like there are a number of O320 engines out there at very reasonable prices when compare to an O360. Could anyone give me an estimate on what the performance figures are for comparison purposes?
Assume a 6A with fixed pitch prop. I might have to go for the O320 with prices being the way they are and availability of decent used mid-time engines.
Oh my, my pet peeve topic, a O320 fixed prop RV6(A) build with in spec weights will fly Wonderfully!
Don't get caught up in the mine is bigger than yours. My O320 RV-4 ran circuls around some 180HP RV's, and I have race results to prove it.
Just go to vans web site and look at the specs, for RV6A. They have performance for solo and gross. You are looking at about going only 8 mph faster and 350 fpm more climb. Keep in mind with a 160 hp you are doing near 200 mph and climbing near 2000 fpm! That is with the 160 HP. Forget all the analysis about fuel burn, better for x-country or what ever, its all about MONEY. Ok A RV6A with 150 or 160 HP is faster than 99% of the certified general aviation single engine planes. I made up the 99%, but if you look a RV6A even with 160 HP is crusing near 190 mph or 165 kts. There are several SE retracts that don't do that!
Price wise, sure a used 320 is going to be cheaper than a 360 on average, apples to apples. I assume you are on a budget, aren't we all.
If buying new it is hard to pass on the 360 since it is almost the same price as a 320. Buying new has almost become the preferred choice.
The salvage yards want WAY too much for used engines. Often they will say it is usable MID-TIME. Unless it's got serious pedigree (Log books and warranty) I would alway be suspicious that its usable as is without rebuild. You DON'T want to fly behind an unknown engine. It could bite you on the today do your first flight or a few years from now with you wife. It is not worth it. If you are going to spend money on your plane, besides the kit cost, get a good engine and go with VFR, day panel and no paint for a while. You can always add a panel or paint. Don't go cheap on the engine. That's my advice. Now cheap does not mean only new, just be warrned.
The thing we have over the salvage guys is we homebuilders have the ability to use many different engine model suffixes. As you probably know a certified airplane MUST have that exact engine, no substitutes. The "Clone" engines we buy are experimental, also not usable by the certified crowd. Clones are a deal. You may consider buying a ECI engine kit and building it yourself with some help. That can save some money and you will learn how the engine is built.
Just remember any used engine you buy, unless you know its condition and even better seen run and checked (compression, oil use per hour and analysis), I consider a core. The core value, top dollar retail is about $5,000. To overhaul is about $10,000 and UP. So for a few thousand more you can have a new clone. Don't buy on impulse and don't buy your engine too soon.
If you are willing not to have the BEST and GREATEST you can look for a 150HP 320, a 320's with conical mounts (usually 150 HP) or a 320-H2AD. You can save a lot.
Just keep in mind that used MID-TIME engine at bargain price is an an illusive animal. A dusty, rusty, spider web engine sitting on an old tire in the corner of a hanger, with no log books sold as MID-TIME, stay a way. Your best scenario is buying from another RV'er who is upgrading their 320 for a 360. Many times you can get prop, baffles, exhaust, oil cooler and so on with the deal saving a lot of money. Of course these deals do not grow on trees.
To answer your question about used engine availability, depends on your ability to hunt them down. Also check out companies that do engine upgrades on Cessna's or Grumman's, I know there are 160 to 180 HP upgrade STC's out there. Find out where they are done. No doubt owners sell their old engines since they can't trade them in. You got to get creative and LOOK for the deals. They will not fall into your lap. It takes time, but you may get lucky.
All these engines 150HP thru 180HP will propel a RV through the sky like (clich? warning) "A home sick angle". Conical mounts are not as good as dynafocal from a vibration standpoint, but if using a wood prop its not a big deal. Even with a metal prop its not that bad, as long as the engine/prop are reasonably balanced. I had a Hartzell extended hub c/s prop on my O320 RV-4 with conical mounts. It was fine after I had my prop properlly balanced and when I discoverd and used "Lord" vibration isolator mounts.
The H2AD has a well known history, but its well known and understood. You can research the H2AD on the web, but they are going to be a better deal. Just don't pay too much for them. The other issue a H2AD has on a RV, is some small mods are needed to install it. Van makes the special engine mount for the H2AD. Also years down the road, you want to upgrade or have more money, you can swap the engine out. Good luck. ITS JUST MONEY YOU CAN'T TAKE IT WITH YOU.
